{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,30]],"date-time":"2026-04-30T16:19:09Z","timestamp":1777565949730,"version":"3.51.4"},"reference-count":14,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2012,8,29]],"date-time":"2012-08-29T00:00:00Z","timestamp":1346198400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/3.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>A microfibre device integrating a microfibre knot resonator in a Sagnac loop reflector is proposed for refractive index and temperature sensing. The reflective configuration of this optical structure offers the advantages of simple fabrication and ease of sensing. To achieve a balance between responsiveness and robustness, the entire microfibre structure is embedded in low index Teflon, except for the 0.5\u20132 mm diameter microfibre knot resonator sensing region. The proposed sensor has exhibited a linear spectral response with temperature and refractive index. A small change in free spectral range is observed when the microfibre device experiences a large refractive index change in the surrounding medium. The change is found to be in agreement with calculated results based on dispersion relationships.<\/jats:p>","DOI":"10.3390\/s120911782","type":"journal-article","created":{"date-parts":[[2012,8,29]],"date-time":"2012-08-29T11:47:52Z","timestamp":1346240872000},"page":"11782-11789","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":59,"title":["Integrated Microfibre Device for Refractive Index and Temperature Sensing"],"prefix":"10.3390","volume":"12","author":[{"given":"Kok-Sing","family":"Lim","sequence":"first","affiliation":[{"name":"Photonics Research Centre, University of Malaya, Kuala Lumpur 50603, Malaysia"}]},{"given":"Iman","family":"Aryanfar","sequence":"additional","affiliation":[{"name":"Department of Electrical Engineering, Faculty of Engineering, University of Malaya, Kuala Lumpur 50603, Malaysia"}]},{"given":"Wu-Yi","family":"Chong","sequence":"additional","affiliation":[{"name":"Photonics Research Centre, University of Malaya, Kuala Lumpur 50603, Malaysia"}]},{"given":"Yew-Ken","family":"Cheong","sequence":"additional","affiliation":[{"name":"Photonics Research Centre, University of Malaya, Kuala Lumpur 50603, Malaysia"}]},{"given":"Sulaiman W.","family":"Harun","sequence":"additional","affiliation":[{"name":"Photonics Research Centre, University of Malaya, Kuala Lumpur 50603, Malaysia"},{"name":"Department of Electrical Engineering, Faculty of Engineering, University of Malaya, Kuala Lumpur 50603, Malaysia"}]},{"given":"Harith","family":"Ahmad","sequence":"additional","affiliation":[{"name":"Photonics Research Centre, University of Malaya, Kuala Lumpur 50603, Malaysia"}]}],"member":"1968","published-online":{"date-parts":[[2012,8,29]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1007","DOI":"10.1364\/OL.35.001007","article-title":"Femtosecond laser fabricated fiber Bragg grating in microfiber for refractive index sensing","volume":"35","author":"Fang","year":"2010","journal-title":"Opt. Lett."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"67","DOI":"10.1364\/OL.37.000067","article-title":"Refractive index sensor using microfiber-based Mach\u2013Zehnder interferometer","volume":"37","author":"Wo","year":"2012","journal-title":"Opt. Lett."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"848","DOI":"10.1109\/LPT.2011.2138126","article-title":"Twisted optical microfibres for refractive index sensing","volume":"23","author":"Liao","year":"2011","journal-title":"IEEE Photon. Technol. Lett."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"2061","DOI":"10.1364\/OL.35.002061","article-title":"Avoided-crossing-based ultrasensitive photonic crystal fiber refractive index sensor","volume":"35","author":"Han","year":"2010","journal-title":"Opt. Lett."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"8200","DOI":"10.1364\/OE.19.008200","article-title":"Optofluidic refractive-index sensor in step-index fiber with parallel hollow micro-channel","volume":"19","author":"Lee","year":"2011","journal-title":"Opt. Express"},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"3817","DOI":"10.1016\/j.optcom.2009.05.079","article-title":"A temperature sensor based on optical microfibre knot resonator","volume":"282","author":"Zeng","year":"2009","journal-title":"Opt. Commun."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"377","DOI":"10.1016\/j.sna.2011.02.036","article-title":"Current sensor based on microfibre knot resonator","volume":"167","author":"Lim","year":"2011","journal-title":"Sens. Actuat. A: Phys."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"143513","DOI":"10.1063\/1.2359439","article-title":"Demonstration of microfiber knot laser","volume":"89","author":"Jiang","year":"2006","journal-title":"Appl. Phys. Lett."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"14217","DOI":"10.1364\/OE.19.014217","article-title":"Optically tunable microfiber-knot resonator","volume":"19","author":"Chen","year":"2011","journal-title":"Opt. Express"},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"191112","DOI":"10.1063\/1.2926672","article-title":"A tunable all-fiber filter based on microfiber loop resonator","volume":"92","author":"Wu","year":"2008","journal-title":"Appl. Phys. Lett."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"2164","DOI":"10.1364\/OL.32.002164","article-title":"Embedding optical microfibre coil resonators in Teflon","volume":"32","author":"Xu","year":"2007","journal-title":"Opt. Lett."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"5912","DOI":"10.1364\/AO.50.005912","article-title":"Resonance condition of a microfibre knot resonator immersed in liquids","volume":"50","author":"Lim","year":"2011","journal-title":"Appl. Opt."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"1098","DOI":"10.1364\/OL.36.001098","article-title":"High finesse microfibre knot resonators made from double-ended tapered fibres","volume":"36","author":"Xiao","year":"2011","journal-title":"Opt. Lett."},{"key":"ref_14","unstructured":"Snyder, A.W., and Love, J. (1983). Optical Waveguide Theory, Chapman and Hall. [1st ed.]."}],"container-title":["Sensors"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1424-8220\/12\/9\/11782\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T21:52:03Z","timestamp":1760219523000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1424-8220\/12\/9\/11782"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2012,8,29]]},"references-count":14,"journal-issue":{"issue":"9","published-online":{"date-parts":[[2012,9]]}},"alternative-id":["s120911782"],"URL":"https:\/\/doi.org\/10.3390\/s120911782","relation":{},"ISSN":["1424-8220"],"issn-type":[{"value":"1424-8220","type":"electronic"}],"subject":[],"published":{"date-parts":[[2012,8,29]]}}}